Resilient mesh material



April 4, 1944. H F. yvE|ss 2,345,844

RESILIENT MESH MATERIL Filed )lay 6, 1941 2 Sheets-Sheet 1 Inventor 7 Hqward W ei ss fcnsfo 'A Nee E`.We55

f- Jaw( M EXECUTE/I @ffy April 4, 1944. H. F. wElss i RESILIENT MESH MATERIAL Filed May 6, 1941 2 Sheets-Sheet 2 hvenl'or award FY We iss DECESFD Patented Apri. 4, 1944 RESILIENT MESH MATERIAL Howard F. Weiss, deceased, late of Madison, Wis., -by Nelle E. Weiss, executrix, Madison, Wis., as-

signor, by mesne assignments, to Research Products Corporation, Madison, Wis., a corporation of Wisconsin Application May 6, 1941,'Serial No. 392,108

17 Claims. (Cl. 117-98) mesh material which is adapted for making pads,

cushions, gaskets and the like, and which has a high coefficient ofrfriction whereby it may be usedv for antiskid purposes, as for example, for nonslip mats or rugs and non-,slip pads for under carpets and rugs, and the like.

Rubber pads and cushions have been used heretofore for similar purposes, ,and it is the object of the invention to provide a new article having improved properties for such purpose.

Briefly, the invention consists informing a fabric in the form of a slitted and expanded sheet composed at least chiefly of rubber, or a material which has the softness, exibility and resilience of vulcanized softrubber. In a fabric of such form, the network is composed of thin, substantially flat, strip-form sections having their broad surfaces disposed angularly to the general plane of the fabric, and when it is composed of a non-rigid resilient material, the result is a product having a relatively high degree of softness and resilience. When the fabric is composed of a material such as vulcanized soft rubber, the resulting fabric possesses softness and resilience in a very high degree and makes an excellent cushioning and padding material.

In accordance' with the invention, the fabric is made by applying a coatingof a rubber` dispersion to a support in the form of slitted and exsections or webs Il whose broad surfaces are disposed angularly to the general plane of the fabric. As shown in Fig. 2, the webs Il are composed of a core l 2 of supporting material, preferably readily flexible, such as paper, and an exterior portion or covering L3 of vulcanized soft rubber, or other material having the softness, exibility and resilience of vulcanized vsoft rubber. By the term sof t rubber it is meant to distinguish from rigid hard rubber. The angular orientation of the webs Il is caused by expanding the slitted sheet transversely of the slits, duringwhich action the webs are turned so that the plane of each individual webis at a substantial angle to the general plane yoi the fabric. When the fabric is subjected to compressive forces exerted perpendicularly to its general plane, it yields by reason of a bending of the webs, which is resisted by their resilience.

- character. This cushioning effect, in general, in-

creases with the degree of expansion. When a l non-stretching material such as paper is used as panded thin sheet material, such as paper, and

Fig. 1 is a plan view of a section of the resilient sheet material of this invention;

I Fig. 2 is a fragmental sectional view along line 2--2 of Fig. 1; u l Fig. 3 is a diagrammatic illustration of an apparatus and method for making the resilient sheet material.

modified forms of the resilient sheet material, and

Figs. 6 and 'I are side views of different forms of matsor cushions composed of a plurality of layers of the resilient sheet material.

The resilient sheet material shown in Fig. 1 is an open-mesh fabric in the form of a slitted and expanded sheet I0. The fabric is composed of a network of thin, substantially flat, strip-form Figs. 4 and 5 are fragmental sectional views of v the expanded supporting means, there is a maxilhaving the degree of softness, flexibility and resilience which is possessed by vulcanized soft rubber, the fabric is characterized by ready flexibility' and a cushioning effect of an exceptionally high order. 'I'he fabric possesses high tensilestrength and resistance to abrasion. In addition, vulcanized soft rubber possesses a high coefficient of friction, and the fabric is very resistant to 4slipping, even when in contact with smooth and slippery surfaces. The product of this invention has the additional advantage that the pattern of the fabric, thateis, the size and shape of the openings and the length, width and' thickness of the webs, maybe varied to suit diiferent applications. In a modification ofthe invention, the apertures of the expanded fabric are closed over with thin rubber films with resulting modication. of properties. This will be described more in detail hereinafter. f'

Inl accordance with the present invention, the resilient material is made by applying a coating of rubber to a supporting fabric of slittedand expanded sheet material, preferably composed of a material which is readily flexible, such as paper,

regenerated cellulose, cellulose acetate,l cellulose.

hydrate, cellulose ethers and 'esters and other substances of cellulose base, in nlm or sheet form, woven or felted cloth, which may be reinforced There is, therefore, an inherent resilience or cushioning effect in a fabric of such and strengthened by impregnating with glue, regenerated cellulose or other nlm-forming material, oil cloth, sheet asbestos, and the like. The material should not be extensible in the manner in which elastic rubber is extensible. As an example, 60 pound kraft paper is a satisfactory material. The slitted7 and expanded sheet material may be 'supplied in the desired width and length. If it is of an inherently resilient material, such as paper, whereby it tends to return to the unexpanded condition, it may be fixed or set in the expanded condition in any suitable manner. Expanded paper maybe set by causing it to be moistened and then dried while in the expanded condition, or by applying stiffening man terials to it, such as glue, resins, etc.

As is illustrated in Fig, 3, the expanded su-pporting material I9 may be supplied in the form of a roll thereof and fedA from the roll over a series of supporting and guide rolls 2|, while operations are performed which will be described. The sheet rst passes into a rubber coagulating bath 22 which may be a dilute aqueous solution of any suitable coagulating agent. An example is a water solution containing 10% calcium chloride, 5% acetic acid and a small amount of a wetting agent, such as soap. Calcium chloride or acetic acid may be used alone and other known rubber coagulating agents may be used. The expanded sheet is coated and impregnated with the coagulating solution, and thence passes into a bath of rubber latex dispersion 23. A water dispersion. containing approximately solids and 0.2% ammonia, is satisfactory, and it may contain a dye or pigment if it is desired to impart a color to the product. It may also contain fillers to impart desired characteristics, such as comminuted reclaimed rubber, silica, asbestos, carbon black, or any other filler commonly employed in rubber products. Dispersions may be employed containing diierent concentrations of solids from that described. The latex may be in either the prevulcanized or unvulcanized condition. If it is in the prevulcanized condition, it need only be dried to be formed into the nal vulcanized soft rubber product. If it is in the unvulcanized condition, it preferably contains the sulfur compounds and accelerators required for vulcanization and may be cured by subjecting it to an elevatedl temperature. A temperature of 80 C. is suflicientand may be applied simultaneously with the subsequent drying operation. In the specic method described, a dispersion of prevulcanized latex is employed. A coating of the latex dispersion is applied to both sides of the slitted and expanded supporting material during the dipping operation. The thickness of 'the coating depends upon the viscosity of the latex dispersion and uniform thickness can best be obtained by maintaining uniform the viscosity, rather than the content, of the dispersion. In this way, non-uniformity in the character of the latex which is sometimes encountered does not affect the coating thickness.

Thelatex dispersion tends to bridge over and ll the apertures of the expanded supporting material, and when a dispersion of the concentration described is used, the apertures are substantially all closed over. To remove the dispersion from the apertures the coated sheet is now passed between a series of air blasts 24. Air under pressure is supplied to conduit system 25 from a source which is not shown. The coated sheet passes vertically downward and the air blasts strike it` alternately from opposite sides as it travels. ,The4

dispersion is removed from the apertures, and shallowv trays or troughs 26 are provided which catch the resulting spray of dispersion and conduct it to a point from which it may be reclaimed for further use.

From the air blasts 24 the coated expanded material is conducted to a second coagulating bath 21 which may be of the same composition as coagulating bath 22. Because of the two applications of coagulating agent, coagulation of the latex proceeds from the interior as well as the exterior ofthe rubber coating. To rid the coating of excess coagulating solution, an air blast 2B is directed against the coated material as it leaves the coagulating bath. The air blast is arranged, as shownso as to return the excess to the coagulating bath.

From the coagulating bath, the coated expanded material' is conducted into a water bath 29, where it is washed substantially free of coagulating agent. After it leaves the washing bath it is` sprayed with clean water from a spray pipe 3B to further cleanse it of coagulatingy agent. The spray water is caused to fall into'the water bath and the latter is provided with an koverflow conduit 3|. The washed sheet may then be subjected to an air blast 32 to remove some of the water which clings to it. i 5

Thence the coated, expanded material passes to a drier 33 which it'is caused to traverse in a suitable manner to accomplish the desired drying of the material. In the particular drier illustrated, the material is conveyed'V therethrough by means of a plurality of conveyors 34 to which it passes in succession. Drying air or gas, preferably heated to an elevated temperature, is circulated through the drier, and the conveyors 34 are composed of an open-mesh material or a plurality of spaced longitudinal strands and permits the ready passage of the drying` gas therethrough.' If an unvulcanized rubber is used, the material is subjected to curing conditions in the drier.

The dried resilient material emerges from the drier 33 and may be accumulated in the form of a roll 35 from which it may be taken for use or sale. The drying need not be entirely completed in the drier 33, it being suilcient if the material is dried tothe point where the adjacent layers Will not stick together Whenit is rolled up on the roll 35. The remainder of the drying is then carried out while the material is in storage. The materialbeing of an open-mesh character, the air circulates freely through it and the roll of material is dried uniformlythroughout.

When the above described methodfor forming the resilient sheet-form material is employed and applied to 60 pound kraft paper, which has a thickness of .006 inch, the thickness'of the product is .022 inch, 'and the rubber coating applied to each side of the expanded sheet-has a thickness of ;0O8 inch.

The specific method described is illustrative only, andthedetails thereof may be varied as desired. For example, instead of applying the coating of latex to the supporting slitted and expanded sheet by a dipping operation, it may bc applied by spraying the latex rsolution against one or both sides of the expanded sheet.

Where the rubber is applied to only one side .of the supporting slitted and expanded sheet material, the supporting sheet may be separated from the rubber fabric aiter the formation ol' .the` latter is complete. This 'may be done by l mechanical means, or where an expanded par :r

supporting sheet material is employed, by washins the fabric with water, which will cause the disintegration of the paper. A fabric 38 of this character is shown in Fig. 4. k

. As another variation of the method, the blowing of air blasts through the sheet material fol#A lowing the coating operation may be eliminated. This will result in thin films of rubber remaining in the apertures of the expanded material. Such a product has particular application where it is desired that the passage of air or gas through it be obstructed or prevented. The softness and resilienceof the product is affected but slightly by the presence of the thin films. A product of this character is illustratedA in Fig. 5, where the network of the expanded material is indicated at 40 and the thin films at 4 l.

In the described method, the first application of coagulating agent causes a setting or coagulating of the coating to proceed from the interior outwardly and with proper regulation of the rate of travel of the material this may be caused to proceed to thev point where further coagulation is unnecessary and the material may pass directly from the air blasts 24 to the drier 33, and the secondnoagulating bath may be dispensed with. In a similar manner, the first coagulating bath may be dispensed with. The employment of two coagulating baths, as described, enables the more rapid carrying out of the process, and imparts a desirable increase in firmness whereby the main portion of the coating is less disturbed while the films are being removed by the air blasts. As a further alternative, instead of employing the first coagulating bath 22, the slitted and expanded sheet material may be impregnated with a coagulati'ng agent at a previous time so that it is in preimpregnated condition at the beginning of the process.

A plurality of layers of the resilient material may be assembled to form a relatively thick pad or cushion. In Fig. 6 a product is illustrated which is composed of a plurality of lsuperposed layers 50 of the resilient material, joined together by a suitable adhesive, such as rubber cement. 'I'he layers may also be joined together by means such as staples, stitching or sewing, etc. The layers may all be of the open-mesh type or of the closed mesh type or a combination may be employed in which some of the layers are of one type and others of the other. For example, the closed and open mesh layers may be arranged in alternating succession.

In Fig. '7 a further modification is illustrated in which layers of the resilient material 55 are arranged in alternating succession with plain imperforate or perforated sheets B. which mav be of rubber, paper, cloth or other sheet material.

In the foregoing description of the invention. rubber is employed as the chief material of which the resilient product is composed, but it is to be understood that other materials having comparable softness, flexibility, resilience and adhesive properties may be used as well. Av suit? able material is the synthetic rubber made `from polymerized isoprene, which has substantially the same properties for the purposes of this invention as does vulcanized soft rubber. The method for applying the synthetic rubber is substantially the same as that described heretofore. When the term rubber is used herein in the specification and claims it is intended to include s uch other materials, as synthetic rubber, having properties similar to those of natural rubber.

What is claimed is:

1. As -a new article of manufacture, a preformed network of rubber having the form of a slitted and expanded sheet.

2. Asa new article of manufacture, a resilient sheet-form product comprising a preformed network having the form of a slitted and expanded sheet, said network being composed essentially of rubber.

3. As a new article of manufacture, a resilient sheet-frmproduct comprising a preformed apertured network having the form of a slitted and expanded sheet, said network being composed essentially of rubber, at least some of the apertures of said network being 4closed over with thin iilms of rubber.

4. As a new article of manufacture, a resilient Y tions having their broad surfaces disposed angularly to the general plane of the fabric, said network being composed essentially of rubber.

v5. As a new article of manufacture, a composite resilient sheet-form product, comprising slitted and expanded sheetmaterial having the flexibility of paper and a coating of rubber on said expanded material.

6. As a new article of manufacture, a composite resilientA sheet-form product, comprising a slitted and expanded brous sheet, and a coating of rubber on said expanded sheet.

7. As a new article of manufacture, a composite resilient sheet-form product, comprising s, slitted and expanded sheet of material having a cellulose' base, and a coating of rubber on said expanded sheet.

8. As a new article of manufacturaa composite resilient sheet-form product, comprising a slitted and expanded paper sheet, and a coating oi.' rubber on said expanded-sheet.

9. As a new article of manufacture, a composite resilient sheet-form product, comprising -a network of thin, stripform sections having their broad surfaces disposed angularly to the general plane of the sheet, said network being composed of a material from the group consisting of fibrous and cellulose base materials, and a coatinar of rubber on said network.

10. As a new article of manufacture, a ma comprising a plurality of layers, each layer comprising a preformed networkhaving theform of a slitted and expanded sheet and being composed essentially of rubber.

11. The method of making a resilient sheetform product, which comprises coating slitted and expanded sheet material from the group consisting of fibrous and cellulose base materials with an aqueous dispersion of rubber, blowing gas through said coated sheet material to open aper. tures thereof which may have been filled by said dispersion, contacting said coating with a rubber coagulating agent, and subsequently water washing and drying said coated sheet material.

` l2. The method of claim ll in which the blasts of gas are blown alternately against opposite sides of the coated sheet material.

13. The method of making a resilient sheetform product, which comprises dipping slitted and expanded sheet material from the group consisting of fibrous and cellulose base materials into an aqueous dispersion of rubber to coat both sides of said sheet material with said dispersion, co-

`agulating said dispersion on said expanded sheet materiaL and drying said coating on said sheet material. n i

14. The method of making a resilient sheetform product, which comprises coating slitted and expanded sheet material having the flexibility of paper with an aqueous dispersion of rubber, and drying said coating on said sheet material.

15. The method of making a resilient sheety form product, Which comprises coating one side of a sltted and expanded sheet material with an aqueous dispersion of rubber, coagulating said dispersion on said expanded sheet material, drying said rubber coating, and separating said rubber coating from said expanded sheet material.

16. The method of making a resilient sheetform product, which comprises applying a coating 15 Eecatri 0f the Estate of Howard F. Weiss, Del ceased. 

